Homeobox B7 accelerates the cancer progression of gastric carcinoma cells by promoting epithelial-mesenchymal transition (EMT) and activating Src-FAK pathway

Long non-coding RNA BBOX1-AS1 exacerbates esophageal squamous cell carcinoma development by regulating HOXB7/β-catenin axis

Mounting evidence suggests that long non-coding RNAs play a critical role in the occurrence and development of human malignancies. Nonetheless, it remains unknown whether Gamma-Butyrobetaine Hydroxylase 1-Antisense RNA 1 (BBOX1-AS1) participates in the regulation of esophageal squamous cell carcinoma (ESCC) carcinogenesis. Herein, we validated that BBOX1-AS1 was notably overexpressed in ESCC tissues compared to the adjacent non-tumor tissues and significantly correlated with tumor sizes. BBOX1-AS1 enhanced the malignant behavior of ESCC cells in vitro, such as cell proliferation, migration, and invasion. In addition, knockdown of BBOX1-AS1 augmented the proportion of apoptotic cells in ESCC cells. Mechanistically, BBOX1-AS1 regulated HOXB7 expression, and rescue experiments indicated that silencing of HOXB7 could abolish the malignant phenotypes mediated by BBOX1-AS1 to a certain extent. Moreover, HOXB7 participated in the activation of the Wnt/β-catenin signaling pathway. In summary, our findings substantiated that BBOX1-AS1 could activate the Wnt/β-catenin pathway by upregulating HOXB7 expression to promote ESCC progression, providing a rationale to develop novel therapeutic approaches.

Identification of Novel Prognostic Markers Associated With Laryngeal Squamous Cell Carcinoma Using Comprehensive Analysis

Background

Laryngeal squamous cell carcinoma (LSCC) is a leading malignant cancer of the head and neck. Patients with LSCC, in which the cancer has infiltrated and metastasized, have a poor prognosis. Therefore, there is an urgent need to identify more potential targets for drugs and biomarkers for early diagnosis.

Methods

RNA sequence data from LSCC and patients’ clinical traits were obtained from the Gene Expression Omnibus (GEO) (GSE142083) and The Cancer Genome Atlas (TCGA) database. Differentially expressed gene (DEG) analysis and weighted gene co-expression network analysis (WGCNA) were performed to identify hub genes. Gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, prognostic value analysis, receiver operating characteristic (ROC) curve analysis, gene mutation analysis, tumor-infiltrating immune cell abundance profile estimation, gene set variation analysis (GSVA), and gene set enrichment analysis (GSEA) were performed. Single-gene RNA sequencing data were obtained from the GSE150321 dataset. Cell proliferation and viability were confirmed by the CCK-8 assay and real-time PCR.

Results

A total of 701 DEGs, including 329 upregulated and 372 downregulated genes, were screened in the GSE142083 dataset. Using WGCNA, three modules were identified to be closely related to LSCC. After intersecting the DEGs and performing univariate and multivariate Cox analyses, a novel prognostic model based on three genes (SLC35C1, HOXB7, and TEDC2) for LSCC was established. Interfering TEDC2 expression inhibited tumor cell proliferation and migration.

Conclusions

Our results show that SLC35C1, HOXB7, and TEDC2 have the potential to become new therapeutic targets and prognostic biomarkers for LSCC.

Downstream of the HOX genes: explaining conflicting tumour suppressor and oncogenic functions in cancer

The HOX genes are a highly conserved group of transcription factors that have key roles in early development, but which are also highly expressed in most cancers. Many studies have found strong associative relationships between the expression of individual HOX genes in tumours and clinical parameters including survival. For the majority of HOX genes, high tumour expression levels seem to be associated with a worse outcome for patients, and in some cases this has been shown to result from the activation of pro-oncogenic genes and pathways. However, there are also many studies that indicate a tumour suppressor role for some HOX genes, sometimes with conclusions that contradict earlier work. In this review, we have attempted to clarify the role of HOX genes in cancer by focusing on their downstream targets as identified in studies that provide experimental evidence for their activation or repression. On this basis, the majority of HOX genes would appear to have a pro-oncogenic function, with the notable exception of HOXD10, which acts exclusively as a tumour suppressor. HOX proteins regulate a wide range of target genes involved in metastasis, cell death, proliferation, and angiogenesis, and activate key cell signalling pathways. Furthermore, for some functionally related targets, this regulation is achieved by a relatively small subgroup of HOX genes.

HOXB7 acts as an oncogenic biomarker in head and neck squamous cell carcinoma

Background

The homeobox gene Homeobox B7 (HOXB7) is overexpressed across a range of cancers and promotes tumorigenesis through varying effects on proliferation, survival, migration and invasion. However, its expression pattern and oncogenic role of HOXB7 in head and neck squamous cell carcinoma (HNSCC) remain largely unexplored. Here, we aimed to explore the expression pattern of HOXB7, its clinical significance as well as functional roles in HNSCC.

Methods

HOXB7 mRNA expression in HNSCC was determined by data mining and analyses from TCGA (The Cancer Genome Atlas) and GEO (Gene Expression Omnibus) datasets. The protein abundance of HOXB7 was measured by immunohistochemistry in 119 primary HNSCC samples and associations between its expression and clinicopathological parameters and patient survival were evaluated. The pro-tumorigenic roles of HOXB7 in HNSCC were further delineated in vitro by loss-of-function assay. And a xenograft tumor model was established in nude mice to assess the role of HOXB7 in tumor growth. Connectivity Map (CMap) analysis was performed to identify bioactive small molecules which might be potential inhibitors for HOXB7.

Results

Bioinformatics analyses showed that HOXB7 mRNA was significantly overexpressed in 8 independent HNSCC datasets from TCGA and GEO databases. HOXB7 protein was markedly upregulated in HNSCC samples as compared to normal counterparts and its overexpression significantly associated with high pathological grade, advanced clinical stage, cervical node metastasis (P = 0.0195, 0.0152, 0.0300) and reduced overall and disease-free survival (P = 0.0014, 0.0007). Univariate and multivariate Cox regression analyses further revealed HOXB7 as an independent prognostic factor for patients’ overall survival. Moreover, HOXB7 knockdown significantly inhibited cell proliferation, migration and invasion and induced cell apoptosis in HNSCC cells, and resulted in compromised tumour growth in vivo. Furthermore, CMap (Connectivity map) analysis has identified three potential bioactive small molecule inhibitors (NU-1025, thiamine, vinburnine) for HOXB7 targeted therapy in HNSCC.

Conclusions

Our findings revealed that overexpression of HOXB7 was associates with tumour aggressiveness and unfavourable prognosis by serving a novel prognostic biomarker in HNSCC. Moreover, HOXB7 might be involved in the development and progression of HNSCC as an oncogene, and thereby might be a potential therapeutic target for HNSCC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-02093-6.

RSF1 in cancer: interactions and functions

RSF1, remodelling and spacing factor 1, is an important interphase centromere protein and is overexpressed in many types of cancers and correlated with poor overall survival. RSF1 has functions mainly in maintaining chromosome stability, facilitating DNA repair, maintaining the protein homeostasis of RSF1 and suppressing the transcription of some oncogenes when RSF1 protein is expressed at an optimal level; however, RSF1 overexpression facilitates drug resistance and cell cycle checkpoint inhibition to prompt cancer proliferation and survival. The RSF1 expression level and gene background are crucial for RSF1 functions, which may explain why RSF1 has different functions in different cancer types. This review summarizes the functional domains of RSF1, the overexpression status of RSF1 and SNF2H in cancer based on the TCGA and GTE_X databases, the cancer-related functions of RSF1 in interacting with H2Aub, HDAC1, CENP-A, PLK1, ATM, CENP-S, SNF2H, HB_X, BubR1, cyclin E1, CBP and NF-κB and the potential clinical value of RSF1, which will lay a theoretical foundation for the structural biology study of RSF1 and application of RSF1 inhibitors, truncated RSF1 proteins and SNF2H inhibitors in the treatment of RSF1-overexpressing tumours.

Long non-coding RNA SNHG8 promotes prostate cancer progression through repressing miR-384 and up-regulating HOXB7

BACKGROUND

Multiple long non-coding RNAs (lncRNAs) have been demonstrated to function as vital regulators in the progression of prostate cancer (PCa). In the present study, we aimed to probe the function of lncRNA small nucleolar RNA host gene 8 (SNHG8) in PCa progression.

METHODS

A quantitative real-time polymerase chain reaction and western blotting were utilized to measure SNHG8, microRNA-384 (miR-384) and homeobox B7 (HOXB7) expression. Call-couting kit-8 and bromodeoxyuridine experiments were employed to evaluate PCa cell proliferation. Transwell experiments were performed to detect PCa cell migration and invasion. Dual-luciferase reporter experiments and RNA immunoprecipitation experiments were conducted to determine the targeting relationships among miR-384, SNHG8 and HOXB7.

RESULTS

SNHG8 was up-regulated in PCa tissues and cells. Silencing of SNHG8 suppressed the proliferation, migration and invasion of PCa cells. SNHG8 functioned as a molecular sponge to repress miR-384. The effects of SNHG8 knockdown on PCa cell proliferation, migration and invasion were counteracted by miR-384 inhibition. HOXB7 was confirmed to be a target gene of miR-384. SNHG8 knockdown repressed HOXB7 expression via targeting miR-384.

CONCLUSIONS

SNHG8 promotes PCa cell proliferation, migration and invasion via decoying miR-384 and up-regulating HOXB7.

Coexpression of HOXA6 and PBX2 promotes metastasis in gastric cancer

HOXA6 gene plays a role of the oncogene in various cancers. Nonetheless, its effect on gastric cancer (GC) occurrence and development is still unclear. We analysed whether HOXA6 interacts with the PBX2 protein using the STRING database. The molecular mechanism by which HOXA6 synergizes with PBX2 in GC metastasis is not fully understood. Here, we found that the expression of HOXA6 was increased in GC tissues and cell lines. The upregulation of HOXA6 was closely associated with differentiation, lymph node metastasis, AJCC stage, TNM stage, and poor survival outcome in GC patients based on tissue microarray (TMA) data. Moreover, the overexpression of HOXA6 promoted, whereas siRNA-mediated repression of HOXA6 inhibited, the cell proliferation, migration, and invasion of GC cells. Furthermore, HOXA6 could physically interact with and stabilize PBX2. In addition, HOXA6 and PBX2 expression was positively correlated in GC cells and tissue. HOXA6 and PBX2 suppression in GC cells also led to decreased migration and invasion potential in vitro. In vivo, HOXA6 was shown to cooperate with PBX2 to enhance cell metastasis via orthotopic implantation. These data indicate that HOXA6 promotes cell proliferation, migration, and invasion and that the HOXA6-PBX2 axis may be a useful biomarker for disease progression in GC.

Galectin-1 promotes vasculogenic mimicry in gastric adenocarcinoma via the Hedgehog/GLI signaling pathway

Background: Galectin-1 (GAL-1), which is encoded by LGALS1, promotes vasculogenic mimicry (VM) in gastric cancer (GC) tissue. However, the underlying mechanism remains unclear.

Methods: Immunohistochemical (IHC) and CD34-periodic acid-Schiff (PAS) double staining were used to investigate Glioma-associated oncogene-1(GLI1) expression and VM in paraffin-embedded sections from 127 patients with GC of all tumor stages. LGALS1 or GLI1 were stably transduced into MGC-803 cells and AGS cells, and western blotting, IHC, CD34-PAS double staining and three-dimensional culture in vitro, and tumorigenicity in vivo were used to explore the mechanisms of GAL-1/ GLI1 promotion of VM formation in GC tissues.

Results: A significant association between GAL-1 and GLI1 expression was identified by IHC staining, as well as a significant association between GLI1 expression and VM formation. Furthermore, overexpression of LGALS1 enhanced expression of GLI1 in MGC-803 and AGS cells. GLI1 promoted VM formation both in vitro and in vivo. The effects of GLI1 on VM formation were independent of LGALS1. Importantly, the expression of VM-related molecules, such as MMP2, MMP14 and laminin5γ2, was also affected upon GLI1 overexpression or silencing in GC cell lines. Conclusion: GAL-1 promotes VM in GC through the Hh/GLI pathway, which has potential as a novel therapeutic target for treatment of VM in GC.

Ephrin B2 mediates high glucose induced endothelial-to-mesenchymal transition in human aortic endothelial cells

Background

Previous study revealed that high glucose (HG) induced endothelial cell (EC) damage via endothelial-to-mesenchymal transition (EndMT). Recent studies suggested the role of Ephrin B2 in mediate ECs damage. However, the underlying mechanism remains unclear. The aim of the present study was to investigate whether Ephrin B2 mediates HG-induced EndMT in human aortic ECs (HAECs) and to determine the possible downstream signaling effector.

Methods

Primary HAECs were exposed to normal glucose (NG, 5.5 mM), HG (30 mM) and HG+Ephrin B2 small interfering RNA (siRNA), respectively. The pathological changes were investigated by light microscope and confocal microscopy. To study the effects of focal adhesion kinase (FAK) activation on Ephrin B2 in HAECs, cells were incubated with FAK siRNA in HG group. The expression of EndMT-related markers (CD31 and FSP1), Ephrin B2 and FAK were detected by qRT-PCR and western blot.

Results

The results showed that HG significantly inhibited the expression of CD31 and increased FSP1 compared with NG group. Moreover, Ephrin B2 was increased after HG incubation. Ephrin B2 siRNA attenuated HG-induced expression of EndMT-related markers. Furthermore, HG increased the expression of FAK and phosphorylated FAK (pho-FAK) in HAECs. In contrast, blocking Ephrin B2 could partially attenuate HG-induced FAK activation. And FAK siRNA further inhibited the EndMT-related markers in HAECs treated with HG.

Conclusions

HG-induced EndMT in HAECs might be partially mediated by Ephrin B2 and the downstream FAK pathway.

Homeobox proteins are potential biomarkers and therapeutic targets in gastric cancer: a systematic review and meta-analysis

BACKGROUND

An increasing number of studies have described the aberrant expression of homeobox (HOX) proteins in gastric cancer (GC), which is critically associated with the prognosis and clinicopathological characteristics of GC. This study was conducted to investigate the clinical value and action mechanisms of HOX proteins in GC.

METHODS

A comprehensive search of PubMed, Embase, Web of Science and Cochrane Library was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement. The pooled hazard ratio (HR) with its 95% confidence interval (95% CI) and the pooled odds ratio (OR) with its 95% CI were used to assess the effect of HOX protein expression on the prognosis and clinicopathological features of GC, respectively.

RESULTS

Nineteen studies containing 3775 patients were selected for this study. Heterogeneity among HRs of overall survival (OS) was markedly high (I2 = 90.5%, p = 0.000). According to the subgroup analysis, increased expression of HOX protein in the downregulated subgroup was associated with a good prognosis for patients with GC (pooled HR: 0.46, 95% CI: 0.36-0.59, I2 = 3.1%, p = 0.377), while overexpression of HOX protein in the upregulated subgroup was correlated with a reduced OS (pooled HR: 2.59, 95% CI: 1.79-3.74, I2 = 73.5%, p = 0.000). The aberrant expression of HOX protein was crucially related to the TNM stage, depth of tumour invasion, tumour size, lymph node metastasis, distant metastasis, vascular invasion, histological differentiation and Lauren classification in patients with GC. In addition, the molecular mechanisms by which HOX proteins regulate tumorigenesis and development of GC were also explored.

CONCLUSIONS

HOX proteins play vital roles in GC progression, which might serve as prognostic markers and therapeutic targets for GC.

Epigenetics mechanisms mediate the miR-125a/BRMS1 axis to regulate invasion and metastasis in gastric cancer

Purpose

Altered expression of breast cancer metastasis suppressor 1 (BRMS1), is a tumor suppressor, which is found in many types of cancers, including gastric cancer (GC), but the mechanism by which BRMS1 inhibits invasion and metastasis in GC is unknown. The aim of the study was to investigate the molecular mechanisms of miR-125a/BRMS1 in GC.

Materials and methods

The expression of BRMS1 and miR-125a were detected by quantitative real-time PCR (qRT-PCR) and analyzed by bioinformatics. BSP and MSP were used to detecte the methylation status of miR-125a and BRMS1 which was treated by 5-Aza or not. Western Blot and qRT-PCR were used to analyze the expression of BRMS1 and EZH2. Transwell was performed to explore the invasion and metastasis ability of GC cells. The nude mice were used for the tumor formation assay.

Results

BRMS1 may be regulated by copy number variation (CNV), methylation and miR-125a-5p. As one of the essential components of PRC2, EZH2 is an important regulatory factor resulting in the low expression of miR-125a. An epigenetic mechanism mediates the miR-125a/BRMS1 axis to inhibit the invasion and metastasis of GC cells. In vivo experiments, it is also showed that BRMS1 is involved in invasion and metastasis but not the proliferation in GC.

Conclusion

These studies shed light on the mechanism of BRMS1 inhibition of GC invasion and metastasis and the development of new drugs targeting the miR-125a/BRMS1 axis, which will be a promising therapeutic strategy for GC and other human cancers.